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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_ccmp.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_ccmp.c')
-rw-r--r-- | drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_ccmp.c | 421 |
1 files changed, 421 insertions, 0 deletions
diff --git a/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_ccmp.c b/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_ccmp.c new file mode 100644 index 000000000..f17d07dad --- /dev/null +++ b/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_ccmp.c @@ -0,0 +1,421 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Host AP crypt: host-based CCMP encryption implementation for Host AP driver + * + * Copyright (c) 2003-2004, Jouni Malinen <jkmaline@cc.hut.fi> + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/random.h> +#include <linux/skbuff.h> +#include <linux/netdevice.h> +#include <linux/if_ether.h> +#include <linux/if_arp.h> +#include <linux/string.h> +#include <linux/wireless.h> + +#include "ieee80211.h" + +#include <linux/crypto.h> +#include <crypto/aead.h> + #include <linux/scatterlist.h> + +MODULE_AUTHOR("Jouni Malinen"); +MODULE_DESCRIPTION("Host AP crypt: CCMP"); +MODULE_LICENSE("GPL"); + +#define AES_BLOCK_LEN 16 +#define CCMP_HDR_LEN 8 +#define CCMP_MIC_LEN 8 +#define CCMP_TK_LEN 16 +#define CCMP_PN_LEN 6 + +struct ieee80211_ccmp_data { + u8 key[CCMP_TK_LEN]; + int key_set; + + u8 tx_pn[CCMP_PN_LEN]; + u8 rx_pn[CCMP_PN_LEN]; + + u32 dot11RSNAStatsCCMPFormatErrors; + u32 dot11RSNAStatsCCMPReplays; + u32 dot11RSNAStatsCCMPDecryptErrors; + + int key_idx; + + struct crypto_aead *tfm; + + /* scratch buffers for virt_to_page() (crypto API) */ + u8 tx_aad[2 * AES_BLOCK_LEN]; + u8 rx_aad[2 * AES_BLOCK_LEN]; +}; + +static void *ieee80211_ccmp_init(int key_idx) +{ + struct ieee80211_ccmp_data *priv; + + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) + goto fail; + priv->key_idx = key_idx; + + priv->tfm = crypto_alloc_aead("ccm(aes)", 0, CRYPTO_ALG_ASYNC); + if (IS_ERR(priv->tfm)) { + pr_debug("ieee80211_crypt_ccmp: could not allocate crypto API aes\n"); + priv->tfm = NULL; + goto fail; + } + + return priv; + +fail: + if (priv) { + if (priv->tfm) + crypto_free_aead(priv->tfm); + kfree(priv); + } + + return NULL; +} + +static void ieee80211_ccmp_deinit(void *priv) +{ + struct ieee80211_ccmp_data *_priv = priv; + + if (_priv && _priv->tfm) + crypto_free_aead(_priv->tfm); + kfree(priv); +} + +static int ccmp_init_iv_and_aad(struct rtl_80211_hdr_4addr *hdr, + u8 *pn, u8 *iv, u8 *aad) +{ + u8 *pos, qc = 0; + size_t aad_len; + u16 fc; + int a4_included, qc_included; + + fc = le16_to_cpu(hdr->frame_ctl); + a4_included = ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) == + (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)); + /* qc_included = ((WLAN_FC_GET_TYPE(fc) == IEEE80211_FTYPE_DATA) && + * (WLAN_FC_GET_STYPE(fc) & 0x08)); + */ + /* fixed by David :2006.9.6 */ + qc_included = (WLAN_FC_GET_TYPE(fc) == IEEE80211_FTYPE_DATA) && + (WLAN_FC_GET_STYPE(fc) & 0x80); + aad_len = 22; + if (a4_included) + aad_len += 6; + if (qc_included) { + pos = (u8 *)&hdr->addr4; + if (a4_included) + pos += 6; + qc = *pos & 0x0f; + aad_len += 2; + } + + /* In CCM, the initial vectors (IV) used for CTR mode encryption and CBC + * mode authentication are not allowed to collide, yet both are derived + * from the same vector. We only set L := 1 here to indicate that the + * data size can be represented in (L+1) bytes. The CCM layer will take + * care of storing the data length in the top (L+1) bytes and setting + * and clearing the other bits as is required to derive the two IVs. + */ + iv[0] = 0x1; + + /* Nonce: QC | A2 | PN */ + iv[1] = qc; + memcpy(iv + 2, hdr->addr2, ETH_ALEN); + memcpy(iv + 8, pn, CCMP_PN_LEN); + + /* AAD: + * FC with bits 4..6 and 11..13 masked to zero; 14 is always one + * A1 | A2 | A3 + * SC with bits 4..15 (seq#) masked to zero + * A4 (if present) + * QC (if present) + */ + pos = (u8 *)hdr; + aad[0] = pos[0] & 0x8f; + aad[1] = pos[1] & 0xc7; + memcpy(&aad[2], &hdr->addr1, ETH_ALEN); + memcpy(&aad[8], &hdr->addr2, ETH_ALEN); + memcpy(&aad[14], &hdr->addr3, ETH_ALEN); + pos = (u8 *)&hdr->seq_ctl; + aad[20] = pos[0] & 0x0f; + aad[21] = 0; /* all bits masked */ + memset(aad + 22, 0, 8); + if (a4_included) + memcpy(aad + 22, hdr->addr4, ETH_ALEN); + if (qc_included) { + aad[a4_included ? 28 : 22] = qc; + /* rest of QC masked */ + } + + return aad_len; +} + +static int ieee80211_ccmp_encrypt(struct sk_buff *skb, int hdr_len, void *priv) +{ + struct ieee80211_ccmp_data *key = priv; + int i; + u8 *pos; + struct rtl_80211_hdr_4addr *hdr; + struct cb_desc *tcb_desc = (struct cb_desc *)(skb->cb + MAX_DEV_ADDR_SIZE); + + if (skb_headroom(skb) < CCMP_HDR_LEN || + skb_tailroom(skb) < CCMP_MIC_LEN || + skb->len < hdr_len) + return -1; + + pos = skb_push(skb, CCMP_HDR_LEN); + memmove(pos, pos + CCMP_HDR_LEN, hdr_len); + pos += hdr_len; + /* mic = skb_put(skb, CCMP_MIC_LEN); */ + + i = CCMP_PN_LEN - 1; + while (i >= 0) { + key->tx_pn[i]++; + if (key->tx_pn[i] != 0) + break; + i--; + } + + *pos++ = key->tx_pn[5]; + *pos++ = key->tx_pn[4]; + *pos++ = 0; + *pos++ = (key->key_idx << 6) | BIT(5) /* Ext IV included */; + *pos++ = key->tx_pn[3]; + *pos++ = key->tx_pn[2]; + *pos++ = key->tx_pn[1]; + *pos++ = key->tx_pn[0]; + + hdr = (struct rtl_80211_hdr_4addr *)skb->data; + if (!tcb_desc->bHwSec) { + struct aead_request *req; + struct scatterlist sg[2]; + u8 *aad = key->tx_aad; + u8 iv[AES_BLOCK_LEN]; + int aad_len, ret; + size_t data_len = skb->len - hdr_len - CCMP_HDR_LEN; + + req = aead_request_alloc(key->tfm, GFP_ATOMIC); + if (!req) + return -ENOMEM; + + aad_len = ccmp_init_iv_and_aad(hdr, key->tx_pn, iv, aad); + + skb_put(skb, CCMP_MIC_LEN); + + sg_init_table(sg, 2); + sg_set_buf(&sg[0], aad, aad_len); + sg_set_buf(&sg[1], skb->data + hdr_len + CCMP_HDR_LEN, + data_len + CCMP_MIC_LEN); + + aead_request_set_callback(req, 0, NULL, NULL); + aead_request_set_ad(req, aad_len); + aead_request_set_crypt(req, sg, sg, data_len, iv); + + ret = crypto_aead_encrypt(req); + aead_request_free(req); + + return ret; + } + return 0; +} + +static int ieee80211_ccmp_decrypt(struct sk_buff *skb, int hdr_len, void *priv) +{ + struct ieee80211_ccmp_data *key = priv; + u8 keyidx, *pos; + struct rtl_80211_hdr_4addr *hdr; + struct cb_desc *tcb_desc = (struct cb_desc *)(skb->cb + MAX_DEV_ADDR_SIZE); + u8 pn[6]; + + if (skb->len < hdr_len + CCMP_HDR_LEN + CCMP_MIC_LEN) { + key->dot11RSNAStatsCCMPFormatErrors++; + return -1; + } + + hdr = (struct rtl_80211_hdr_4addr *)skb->data; + pos = skb->data + hdr_len; + keyidx = pos[3]; + if (!(keyidx & BIT(5))) { + if (net_ratelimit()) { + netdev_dbg(skb->dev, "CCMP: received packet without ExtIV flag from %pM\n", + hdr->addr2); + } + key->dot11RSNAStatsCCMPFormatErrors++; + return -2; + } + keyidx >>= 6; + if (key->key_idx != keyidx) { + netdev_dbg(skb->dev, "CCMP: RX tkey->key_idx=%d frame keyidx=%d priv=%p\n", + key->key_idx, keyidx, priv); + return -6; + } + if (!key->key_set) { + if (net_ratelimit()) { + netdev_dbg(skb->dev, "CCMP: received packet from %pM with keyid=%d that does not have a configured key\n", + hdr->addr2, keyidx); + } + return -3; + } + + pn[0] = pos[7]; + pn[1] = pos[6]; + pn[2] = pos[5]; + pn[3] = pos[4]; + pn[4] = pos[1]; + pn[5] = pos[0]; + pos += 8; + + if (memcmp(pn, key->rx_pn, CCMP_PN_LEN) <= 0) { + if (net_ratelimit()) { + netdev_dbg(skb->dev, "CCMP: replay detected: STA=%pM previous PN %pm received PN %pm\n", + hdr->addr2, key->rx_pn, pn); + } + key->dot11RSNAStatsCCMPReplays++; + return -4; + } + if (!tcb_desc->bHwSec) { + struct aead_request *req; + struct scatterlist sg[2]; + u8 *aad = key->rx_aad; + u8 iv[AES_BLOCK_LEN]; + int aad_len, ret; + size_t data_len = skb->len - hdr_len - CCMP_HDR_LEN; + + req = aead_request_alloc(key->tfm, GFP_ATOMIC); + if (!req) + return -ENOMEM; + + aad_len = ccmp_init_iv_and_aad(hdr, pn, iv, aad); + + sg_init_table(sg, 2); + sg_set_buf(&sg[0], aad, aad_len); + sg_set_buf(&sg[1], pos, data_len); + + aead_request_set_callback(req, 0, NULL, NULL); + aead_request_set_ad(req, aad_len); + aead_request_set_crypt(req, sg, sg, data_len, iv); + + ret = crypto_aead_decrypt(req); + aead_request_free(req); + + if (ret) { + if (net_ratelimit()) { + netdev_dbg(skb->dev, "CCMP: decrypt failed: STA=%pM\n", + hdr->addr2); + } + key->dot11RSNAStatsCCMPDecryptErrors++; + return -5; + } + + memcpy(key->rx_pn, pn, CCMP_PN_LEN); + } + /* Remove hdr and MIC */ + memmove(skb->data + CCMP_HDR_LEN, skb->data, hdr_len); + skb_pull(skb, CCMP_HDR_LEN); + skb_trim(skb, skb->len - CCMP_MIC_LEN); + + return keyidx; +} + +static int ieee80211_ccmp_set_key(void *key, int len, u8 *seq, void *priv) +{ + struct ieee80211_ccmp_data *data = priv; + int keyidx; + struct crypto_aead *tfm = data->tfm; + + keyidx = data->key_idx; + memset(data, 0, sizeof(*data)); + data->key_idx = keyidx; + if (len == CCMP_TK_LEN) { + memcpy(data->key, key, CCMP_TK_LEN); + data->key_set = 1; + if (seq) { + data->rx_pn[0] = seq[5]; + data->rx_pn[1] = seq[4]; + data->rx_pn[2] = seq[3]; + data->rx_pn[3] = seq[2]; + data->rx_pn[4] = seq[1]; + data->rx_pn[5] = seq[0]; + } + if (crypto_aead_setauthsize(tfm, CCMP_MIC_LEN) || + crypto_aead_setkey(tfm, data->key, CCMP_TK_LEN)) + return -1; + } else if (len == 0) { + data->key_set = 0; + } else { + return -1; + } + + return 0; +} + +static int ieee80211_ccmp_get_key(void *key, int len, u8 *seq, void *priv) +{ + struct ieee80211_ccmp_data *data = priv; + + if (len < CCMP_TK_LEN) + return 0; + + if (!data->key_set) + return 0; + memcpy(key, data->key, CCMP_TK_LEN); + + if (seq) { + seq[0] = data->tx_pn[5]; + seq[1] = data->tx_pn[4]; + seq[2] = data->tx_pn[3]; + seq[3] = data->tx_pn[2]; + seq[4] = data->tx_pn[1]; + seq[5] = data->tx_pn[0]; + } + + return CCMP_TK_LEN; +} + +static char *ieee80211_ccmp_print_stats(char *p, void *priv) +{ + struct ieee80211_ccmp_data *ccmp = priv; + + p += sprintf(p, "key[%d] alg=CCMP key_set=%d tx_pn=%pm rx_pn=%pm format_errors=%d replays=%d decrypt_errors=%d\n", + ccmp->key_idx, ccmp->key_set, + ccmp->tx_pn, ccmp->rx_pn, + ccmp->dot11RSNAStatsCCMPFormatErrors, + ccmp->dot11RSNAStatsCCMPReplays, + ccmp->dot11RSNAStatsCCMPDecryptErrors); + + return p; +} + +static struct ieee80211_crypto_ops ieee80211_crypt_ccmp = { + .name = "CCMP", + .init = ieee80211_ccmp_init, + .deinit = ieee80211_ccmp_deinit, + .encrypt_mpdu = ieee80211_ccmp_encrypt, + .decrypt_mpdu = ieee80211_ccmp_decrypt, + .encrypt_msdu = NULL, + .decrypt_msdu = NULL, + .set_key = ieee80211_ccmp_set_key, + .get_key = ieee80211_ccmp_get_key, + .print_stats = ieee80211_ccmp_print_stats, + .extra_prefix_len = CCMP_HDR_LEN, + .extra_postfix_len = CCMP_MIC_LEN, + .owner = THIS_MODULE, +}; + +int __init ieee80211_crypto_ccmp_init(void) +{ + return ieee80211_register_crypto_ops(&ieee80211_crypt_ccmp); +} + +void ieee80211_crypto_ccmp_exit(void) +{ + ieee80211_unregister_crypto_ops(&ieee80211_crypt_ccmp); +} |